新型含吡啶单元给受体共轭聚合物/TiO_(2)复合材料的制备及其在紫外光电探测器中的应用

Preparation of Novel Donor Acceptor Conjugated Polymer/TiO_(2) Composite Containing Pyridine Unit and Its Application in UV Photodetectors

以3,4-丙撑二氧噻吩封端,吡啶为中间单元的三联体为单体(3,4-丙撑二氧噻吩为给体单元、吡啶为受体单元),制备新型含吡啶单元给受体共轭聚合物/TiO_(2)复合材料,并将复合材料应用在紫外光探测上.采用UV-vis、XRD、FT-IR、XPS、SEM等测试方法对材料进行结构表征,通过测试Tafel、I-T等曲线研究器件的紫外光探测器性能.当外界偏压为1~6 V时,研究了给受体型共轭聚合物(PProDOT-Py)结构中吡啶基团与TiO_(2)纳米阵列(NRs)之间的协同作用.结果表明:当偏压为5 V时,PProDOT-Py和TiO_(2)NRs复合材料具有快速的时间响应(T_(rise)=8 s、T_(fall)=18 s)、高响应(696.8 mA/W)、高探测能力(1.23×10^(11)cm·Hz^(1/2)·W^(-1))和高外量子效率(237.1%).

A novel conjugated polymer/TiO_(2) composite containing pyridine unit as donor acceptor was prepared by using 3,4-propylenedioxythiophene as terminal block and pyridine as intermediate unit as monomer(3,4-propylenedioxythiophene as donor unit and pyridine as acceptor unit).The composite was applied to UV detection.UV Vis,XRD,FT-IR,XPS,SEM and other test methods were used to characterize the structure of the material.The UV detector performance of the device was studied by testing Tafel and I-T curves.The synergistic effect between pyridine group in donor acceptor conjugated polymer(PProDOT-Py)structure and TiO_(2) nano arrays(NRs)was studied in detail.Because the pyridine unit on PProDOT-Py can form a coordination bond with TiO_(2) NRs,there is a synergistic effect between PProDOT-Py and TiO_(2) NRs.This structure promotes the formation of donor acceptor structure,thus improving carrier conversion,reducing carrier recombination and effectively separating electron hole pairs.The results show that when the bias voltage is 5 V,PProDOT-Py and TiO_(2) NRs composites have fast time response(T_(rise)=8 s,T_(fall)=18 s),high response(696.8 mA/W)and large detection capability(1.23×10^(11)cm·Hz^(1/2)·W^(-1)),and high external quantum efficiency(237.1%).